Friction clutch



- April 26, 1938. R. A. CARLSON FRICTION CLUTCH Filed Dec. 1, 1956 2 Sheets-Sheet l ZZZ/6722 62" iq 07720720. CZ 6672:5072 i g4 A April 26, 1938. R CARLSQN 1 2,115,252 J FRICTION CLUTCH 2 Sheets-Sheet 2 7 Filed Dec. 1, 1956 Patented Apr. '26, 1938 UNITED STATES FRICTION CLUTCH Raymond A. Carlson, Rockford, Ill., assignor to Borg-Warner Corporation, Chicago, Ill.,

poration of Illinois a OOY- Application December 1, 1936, Serial No. 113,593

6 Claims.

This invention relates to friction clutches and is concerned more particularly with a power transmitting spring loaded clutch of the toggleoperated type.

It is an object of my invention to provide an improved spring loaded clutch of the toggle-operated type which requires relatively little manual effort to effect clutch release and to hold the clutch in full release position, yet which employs relatively heavy pressure plate operating springs.

It is another object of the invention to provide in a clutch of the character described a toggleoperated clutch release mechanism which is operative without requiring over-center movement of the mechanism.

Further objects and advantages of the invention will appear as the description proceeds.

An illustrated embodiment of the invention scribed hereinafter. In the drawings:

Fig. 1 is a rear plan view of a clutch embodying the invention, portions thereof being broken away;

Fig. 2 is a longitudinal fragmentary sectional 5 view taken substantially as indicated by the line II-II in Fig. 1; and V Fig. 3 is a longitudinal fragmentary sectional view taken substantially as indicated by the line IIIIII in Fig. 1, but showing the parts as they appear when the clutch is disengaged.

Referring more particularly to the drawings, the flywheel I or other suitable driving member is engageable with a driven clutch plate 2 carried by the clutch shaft 3, the clutch plate 2 be- 5 ing urged against the flywheel by a spring-urged pressure plate 4. A cover plate 5, secured at 6 to the flywheel has a key-like connection at l with the pressure plate to drive the latter, but to permit of its axial movement, and is provided with a plurality of circular recesses 8 substantially registering with corresponding recesses 9 in the pressure plate to house an outer relatively heavy spring II] and an inner relatively light spring II.

there is a pin I3 having a reduced tall portion I4 telescoped within the inner spring II and providing a shoulder I5 forming an abutment for one end of theinner spring II. The pressure plate 4 has a rearwardly extending sleeve IE to which is threaded an adjusting nut, or plate, I! engageable by clutch releasing means, the description of which appears hereinafter. The plate I1 is provided on its forward face with notches I8, one for each pin I3, and each pin has its rear end taperedto form a V-nose IS adapted to be held by the spring II in a corresponding notch I8 and to cooperate ratchetwise therewith. A lug 20 projecting from each pin I3 into a slot 2| in the plate 5 prevents the nose I9 of appears in the accompanying drawings and is de- Extending through the bottom of each recess 8 each pin from turning out of register with the notches I8. The rear face of the plate I! is provided with a plurality of notches 22 engageable by a suitable tool for manual adjustment by rotation of the plate about the sleeve I6. Such rotation of the plate is accompanied by ratchet movement of the pins I3 associated with the notches I8, the plate being brought to rest with each pin I3 disposed in a notch I8. This mechanism operates therefore not only to vary the adjustment of the plate I! relative to the pressure plate 4, but to maintain the plate I! against accidental displacement. I

Means for releasing the pressure plate 4 against the compression of the springs I0 may comprise a collar 23, having trunnions 24 to be received by a fork (not shown) operated by the foot of the driver against the action of the usual fork spring to effect the release of the clutch, and adapted, upon release of the clutch pedal by the driver, to permit engagement of the clutch. .The collar 23 issecured to a sleeve 25 provided with a plurality of arms 26 having forked ends 21 bridged by a pivot pin 28 about which an anti-friction sleeve roller 29 is fitted, the roller 2% being fitted in the slot 36 of a bell crank lever 3|. The lever 3| passes through a slot 3Ia in the pressure plate sleeve I6 and terminates in a rod portion 32 having its ends journalled in anti-friction bearing means 33 carried by the cover 5. A thrust arm 34 is carried one at each end portion of the rod 32. Each arm 34 has a rounded bearing end 35 slidably engageable with a correspondingly shaped concavity .36 in a thrust member 3'! whose outer end is cam-shaped as shown at 38 for engagement with the forward face 39 of the adjusting plate H. The thrust members 31 are provided with opposed trunnions 4t) slidably and rotatably received in opposed slots 4| in the back plate 5 so that upon shift of the sleeve 23 in the forward direction, indicated by the arrow 42 in Figure 2, the thrust arms 34 will impart acombined rearward sliding and counterclockwise movement to the thrust members 31, as viewed inFlg. 2, the cam surfaces 38 of which will be forced against the inner surface 39 of the plate I-l, causing the plate and with it the pressure plate 4 to recede from'the driven clutch plate 2, thereby to release the clutch against the compression of the pressure plate springs I0.

As will be observed from Figs. 2 and 3, the action of this mechanism is substantially a toggle action, and when the sleeve 23 reaches the limit of its forward movement, the toggle mechanism is at or short of dead center, as seen in Fig. 3. The slots 4| are of such length that they do not interfere with the sliding movement of the trunnio-ns 40 throughout the limits of movement of the members 31 against the plate H. In order that the toggle mechanism including the thrust V engagementrm ay be effected upon drawing the members 31 and arms 34 may notpass beyond the inner'end portions of the thrust members may rest (as shown in Fig. 3) when the clutch is in its fully released position. V I

While I have illustrated a mechanism bywhich the clutch is released in response tothrust applied to'thee collar 23, it will be appreciated that by a mere reversal 'ofarrangement, clutch discollar.

trucks and for. other heavy duty purposes, and when so employed, itssprings l0 may be considerably stronger than those found in conventional passenger automobile clutches. 7 V

' When theclutch is engaged, the springs l9 V maintain engagement until manualor power disengagement is brought about through the toggle mechanism'.- Once the clutch'is disengaged-the Clearance; preferably not more than is g V 'afiordedbetweenthethrust members 31 and the 1 plate l1 yvhen the'clutch is engaged, to provide a :slight lost motion offithe clutch releasesleeve 23 V aozpreparatory to the commencement of the disen 'togg1e arrangement is suchas to maintain disengagement with relatively little'manual 'efiortL gaging action. 7

I claim:

3 15A clutch; for motor, vehicles comprising acover plate, a pressure plate located on'the inner mechanism one member of which 1s engageable i ggfiside of said 'cover plate and adapted tomove axially thereof, compression springs interposed be-f tween said pressure plate and said cover plate, an

operating plate located on the outersideof said varied at will, and clutch release means associ ated "with said cover pl'ateincluding a toggle with said operating plate for applying thrust to said operating plate ina direction against the" force of semi-d compression springs when the toggle,

" movement on one side only of its dead center.;

mechanism is moved toward its dead center.

7 2. A clutch for motor vehicles comprising a 'cover plate, 'apressure plate located on the inner side of .said cover plate and adapted to move axially thereof, compression springsinterposed said cover plate and parallel with said pressure will, and clutch. release means associated with saidrc'over plateincluding a plurality jof'toggle means each having two arms, one engageable with said operating platejand theother pivoted on said cover plate, and common means for operating said toggle "means simultaneously thereby to transmitthrustfto said operating plate at a plurality of distributed'points.

3. A motor vehicle clutch comprising a cover,; a pressure plate mounted'on the inner side of-said cover, said pressure plate ,havingfa central p01? This clutch structure is adapted for use in' said pressure plate.

cover plate and parallel with said pressure plate, 7 spring-restrained adjustable'means securing said 7 "foperating plate against movement relative to said pressure platewhereby the distance between said f. pressure'plate andrsaid operating plate'may be 7 between said pressure plate and said cover plate,. an operating plate located on the outer 'side of tion extending through an opening insaid cover,

an operating plate located on the outer side of said cover, and having screw thread engagement.

with said last named pressure plate portion whereby the. operating plate may be moved "toward and away from saidpressure plate at will,

means associated with said cover and said operating plate for locking said 7 operating plate against movement relative to, said pressure plate,

toggle mechanism including a member engageable with said operating plate and a member 7 having an operating arm and means adapted for 7 manual control to move said arm whereby to operate said toggle mechanism thereby to move 4. A'motor vehicle-clutch comprising a cover,

a pressure plate mounted on the innerside of 'said cover, said pressure plate having a central portionextending through an opening in said cover,=an;

operating plate located oritheouter side ofsaid cover, andhaving screw thread engagement with Y said last named-pressure plate portion whereby the operating plate I may be moved towardfand e away from said pressure plate at"will,;means* locking said operating :plate against movement" relative'to said pressure plate, toggle mechanism move said arm whereby to operatevsaid toggle mechanism thereby to'move' said pressure plate,

said toggle mechanism being mounted upon said, cover; and including means preventing the movementof the toggle, mechanism beyond its dead center.

5. A motor vehicle clutch comprising a coveria pressure plate located on thevinner sideof said cover, compression springs urging said pressure,

plate in a directionaw'ayfrom said cover along p the longitudinal'axis thereof, an operating plate located on the outer side of said cover inparallels.

relationshipto said pressure plate; toggle mecha- "nism carried 'by said cover, having one of the elements thereof engageable with said operating.

plate, the other; element of said toggle mechanism having an arm extending-therefrom,'manually operated means for moving'said arm whereby to" r operate said toggle mechanism,and means limit-1 ing the operation of said toggle mechanism to 6. A motor vehicle clutch comprising a cover, 1 a pressure plate mounted on the inner side ofsaid cover, said pressure eplate ha ving a central pork tion extending through an opening in said cover, 7 7

an operating platelocatedon' the .outer sideiof said cover, and having screw thread'engagement with 1 said 'last named pressure plate portion means locking saidoperating plate'against move ment' relative to said pressure plate, toggle mech-" anism including a member engageable withsaid operating. plateand a member having. an'operating arm' and means adapted for manual con trol to move said arm'wherebytooperate 'said' toggle mechanism thereby to, move said pressure I plate, said toggle mechanism including said member engageable with the operating plate and said operating arm being wholly disposed between the operating plate and the pressure plate.

RAYMOND'A. cARLsoN; 

